devpreview.me

Open a JSON API response, a YAML config, an XML feed or a minified stylesheet in Chrome and you get a wall of unformatted text. devpreview.me turns it into something you can actually read — and then leaves every other page alone. Each of the eight formats it recognises gets the views that format deserves: • Rendered — syntax colours, collapsible nodes, virtual scrolling that stays fast on files with tens of thousands of lines • Schema — the shape of the data instead of the data: which keys exist, how often, of which type, with a click to copy any path • Values — any array that the schema cannot open further becomes a sortable table, with a count of distinct values per column • Map — coordinates found anywhere in the file, drawn on a world map that ships inside the extension. No tiles are loaded, no map service learns which region you are looking at. Click a point and its coordinates are on your clipboard. • Feed, Sitemap and API — RSS and Atom as a readable feed, sitemaps as a list of addresses, OpenAPI as its operations grouped by path CSS and JavaScript get the two views a stylesheet and a program need: • A minified file is pulled apart again — line breaks and indentation restored, syntax coloured, every bracket foldable. A click copies the piece that belongs together: a CSS value alone, a property name with its whole declaration, a selector with the entire rule. In JavaScript a function's name copies the call as you would have to write it, including the await; the word "function" in front of it copies the whole function. • Profile — what a stylesheet declares, and what only measuring can answer. Colours split by what they do, custom properties resolved to the value they end up being, every font size with its line heights, weights, colours and measured contrast, the spacing and radius scales, the breakpoints. Every number opens the selectors behind it. • API — what a JavaScript file declares: its classes with their members, its functions with what each one hands back — nothing, a value, a promise, or itself — its module-level values, and every event it listens for, with what runs and how the listener was registered. A file is recognised by what it contains, not only by its extension, so one served as plain text still opens in the view that suits it. And some files are more than their syntax: XSD and WSDL open as the definitions they declare, a plist as the settings it holds, an OPML file as the outline it is. KML and GPX show their places and tracks, GeoJSON and TopoJSON draw their features on the map. JSON Lines opens as the records it streams, and TSV as the table it already was. One search box searches whatever you are looking at, including the schema and the raw source. CSV can be exported in a form Excel opens correctly on a European system, with formula injection defused. Nothing leaves your machine. No account, no server, no analytics, no telemetry. The only host devpreview.me contacts is the one whose file you opened — the same request the browser was making anyway. Free, with no account and nothing to sign up for: https://www.devpreview.me